Yet another version of the Bagle worm is on the loose and is already causing trouble in parts of Europe. Bagle.U appeared early Friday morning and has begun spreading quickly, even though it contains none of the social engineering tricks that Bagle's author has used to help previous versions succeed.
This variant arrives in an e-mail with a blank subject line and no body text. The sending address, as always, is spoofed, and the name of the infected executable attachment is completely random. After execution, the worm mails itself to all of the addresses in the infected machine's address book.
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